Visiting the Largest Volcano in the World

If visiting the world's largest volcano sounds dangerous, think again: not all volcanoes erupt with abandon and leave towns covered in molten lava and ash.

While it’s certainly true that volcanoes, like Mount Tambora in Indonesia (on record as the world’s deadliest) and Mount Vesuvius in Italy (one of the world’s most active), do indeed pose threats, many volcanoes are far less dramatic. Such is the case with Hawaii’s Mauna Loa, which happens to be the world’s largest active volcano, by both volume as well as size.

Head to Hawaii

Mauna Loa is located on the island of Hawaii, which is the largest island in the archipelago itself—it’s name means “long mountain” in Hawaiian. Along with four other volcanoes, it forms the very structure of the island. Mauna Loa is considered a shield volcano, meaning that was created by the flow of lava over time. Such volcanoes are not particularly tall (at least in the world of volcanoes). Instead, they grow wide likes shields (hence the name). When measured, Mauna Loa's lava tallies more than 56,000 feet, though its actual elevation is only 13,679 feet.

It’s theorized that the island of Hawaii (or Big Island, as it’s sometimes called) took nearly one million years to form. It began when the island’s five volcanoes erupted through the ocean floor. Geologists estimate that Mauna Loa has been erupting for some 700,000 years and peaked its head above water just 400,000 years ago. Today, Mauna Loa continues to expel lava, thus adding acreage of the ever-expanding island.

Don't Worry About Eruptions

But what can be said of Mauna Loa explosions? Quite simply, Mauna Loa doesn’t have them. Deemed a non-explosive volcano due to the low silica content of its lava, Mauna Loa has very fluid eruptions. Native Hawaiians have been present on the island for about 1,500 years, but left little record of volcanic activity from Mauna Loa. The last eruption was in 1984, when lava flow emerged from the summit and headed downslope toward Hilo, the island’s largest city. The lava missed city limits by roughly four miles, but was so bright that it illuminated the city at night. Since then, Mauna Loa has been pretty quiet, though experts claim to see signs that it may wake in the near future.

Visit the National Park

Until then, Moana Loa is an extremely popular tourist destination, attracting some two million visitors each year to Hawaii's Volcanoes National Park. Come here to walk through lava tubes, enjoy more than 150 miles of hiking trails, and watch a volcano erupt. It's not Moana Loa that's doing the erupting, of course—it's the neighboring volcano, Kilauea, which is currently erupting from two places.

Mauna Loa also holds the distinction of being part of a volcano club, of sorts. The International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI) included Mauna Loa in a group of sixteen volcanoes, known as Decade Volcanoes. Such volcanoes are of particular interest because of both their high levels of activity and their proximity to large population centers. Washington’s Mount Rainier and Sicily’s Mount Etna also made the list.

But perhaps most interestingly, Mauna Loa has some competition for the crown of largest volcano. That is, on the Earth's surface. Roughly 1,000 miles east of Japan is an extinct volcano dubbed Tamu Massif—which lies underwater. Its discovery was announced just recently in 2013. And the tallest? Neighboring Mauna Kea, a dormant volcano on the Big Island that stands just a couple hundred feet higher (surpassing Everest by a mile, if you consider how much of the volcano is submerged below sea level).

When it comes to volcanoes, size doesn't matter as much as their temperament.